Automatic test tube transporter and sample dispenser

ABSTRACT

An automatically operated transporter apparatus which advances racks containing double rows of test tubes under a vertically movable aspirating and dispensing tip and tilts the tubes successively to a reference position allowing the tip to descend and engage the inner side wall of the tubes to perform its function. The tip is operationally in communication with a double pump metering and dispensing apparatus which includes a linearly adjustable eccentric mechanism which drives the pump pistons with a motion of adjustable sinusoidal amplitude. The apparatus also includes a pump valve switching mechanism which automatically switches the valves and the ports on the pumps between suction and compression strokes. The pumps may be adjusted to either work in parallel or alternating strokes. An automatic tip wiping mechanism is provided to insure precision in the processing. The apparatus can be set for continuous operation or for individual test tube processing cycle operation. Empty racks can be advanced without engaging the tip and pump apparatus. A trouble relay system gives a warning in case of any malfunction and stops the apparatus in most cases.

United States Patent 1 Sanz et al.

[ AUTOMATIC TEST TUBE TRANSPORTER AND SAMPLE DISPENSER [76] inventors:Manuel C. Sanz, 50B Chemin des Verjus, Geneva, Switzerland; Byron E.Sturgis, 1806 Epworth Dr., Hunstville, Ala. 35811; Charles V. Lawson,304 Fifth St. NE, Arab, Ala. 35016; Joe K. Bain, 2307 Rosemont St.,Decatur, Ala. 3560] [22] Filed: Mar. 22, 1971 [21] Appl. No.: 126,782

[30] Foreign Application Priority Data Apr. 3, 1970 Canada 79,112

[52] 11.8. C1. 141/130, 23/230, 23/253, 23/259, 73/425.6,141/90,141/125,141/167, 141/181, 141/168 [51] Int. Cl 1365b 43/56 [58] Field of Search23/253, 259, 230; 356/246; 250/218, 220; 73/425.6; 141/90, 125,167,168,181, 130

[56] References Cited UNITED STATES PATENTS 3,622,279 11/1971 Moran141/130 Primary Examiner-Houston S. Bell, Jr. AtIomeyGerry J. Elman,Carl A. Castellan and George W. F. Simmons [57] ABSTRACT Anautomatically operated transporter apparatus which advances rackscontaining double rows of test tubes under a vertically movableaspirating and dispensing tip and tilts the tubes successively to areference position allowing the tip to descend and engage the inner sidewall of the tubes to perform its function. The tip is operationally incommunication with a double pump metering and dispensing apparatus whichincludes a linearly adjustable eccentric mechanism which drives the pumppistons with a motion of adjustable sinusoidal amplitude. The apparatusalso includes a pump valve switching mechanism which automaticallyswitches the valves and the ports on the pumps between suction andcompression strokes. The pumps may be adjusted to either work inparallel or altemating strokes. An automatic tip wiping mechanism isprovided to insure precision in the processing. The apparatus can be setfor continuous operation or for individual test tube processing cycleoperation. Empty racks can be advanced without engaging the tip and pumpapparatus. A trouble relay system gives a warning in case of anymalfunction and stops the apparatus in most cases.

49 Claims, 40 Drawing Figures 'PATENTEDBUIBOHH 3.768.526

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' SHEET 130F 19 PATENTEUHCI 30 I915 SHEET ISUF 19 OPERATIONPMFNTEHUCIBOISH I I 3,768,526

SHEET 16 F 19 MANUAL J1 SWITCH AUTOMATIC I SWITCH ADVA CE J I TIP DOWN II J' L TIP UP TRANSPORTER TEETH J 20 TEETH l r- STNTEERVAL VALVE H PUMPTEETH L J' lllllIll lllflllll llllll ll lllllll 0.0 I.0 I5 2.0 25

IDLE GEAR R0TATI0N (DEGREESWTIME (sec) A 810 VE I MANUAL SWITCH 807 PUMPOPERATION PATENTEUHU 30 1915 3.768526 SHEET UN 19

1. An automatic apparatus for processing samples contained in aplurality of tubes mounted in a support rack comprising a base having aplanar surface, at least one conduit having an aspirating and dispensingtip, means to raise and lower said tip relative to the base, meanssupporting said tip and the tip raising and lowering means above saidplanar surface, pump means of adjustable volumetric capacity incommunication with said conduit means and comprising at least two pumpseach having a cylinder and piston means, said pistons beingconstantdisplacement pistons of constant cross-section to provideaccurate, positive displacement increments, stroke-adjustment means forindividually varying the length of stroke of each of said pistons, motormeans, eccentric means connecting said motor means to saidstroke-adjustment means, said eccentric means being constructed toprovide sinusoidal aspirating and dispensing pressures to said tip, rackadvancement means to move a loaded support rack underneath said tip byincrements so as to position each tube for lowering of said tip andcycling of said pump means, said pump means adapted to providesinusoidal aspirating and dispensing pressures to said tip only whensaid tip is in the down position, and electrical means to control theoperation of said motor means, pump means and said rack advancementmeans and to cycle said pump means and said tip means automatically uponoperation of said rack-advancement means.
 2. An apparatus as in claim 1including guide means on said planar surface adapted to automaticallyfeed said support racks to said rack advancement means, whereby aplurality of loaded racks may be automatically processed.
 3. Anapparatus as in claim 2 wherein said guide means comprises parallelrails on said planar surface, said rails having slot means therein,rack-pushing means between said rails and mounted for sliding movementin said slot means.
 4. An apparatus as in claim 3 wherein a tensioningmeans is provided to put tension on said rack pushing means to bias ittoward said rack advancement means.
 5. An apparatus as in claim 1including means associated with the stroke adjustment means and motormeans whereby the pUmp pistons can be set to either pump in parallel orin alternately opposite directions.
 6. An apparatus as in claim 1wherein said eccentric means is linearly adjustable to set the pistonsstroke from zero to a predetermined maximum.
 7. An apparatus as in claim6 including external indicator means on said apparatus to indicate thestroke setting on each eccentric mechanism.
 8. An apparatus as in claim1 wherein there are two ports in each cylinder, valve means in each pumpcapable of alternately placing said cylinder in communication with oneport for the intake stroke and the other port during the exhaust stroke,said valve means being driven by said motor means.
 9. An apparatus as inclaim 8 wherein each pump is constructed so that said pistons andcylinders may be easily removed and replaced with cylinders and pistonsof different constant cross section.
 10. An apparatus as in claim 8wherein at least one of said pumps has a bleed and priming meansassociated with its cylinder.
 11. An apparatus as in claim 8 whereineach said valve means includes a rotary member and a valve switchingmechanism in operative association with each said rotary member and saidmotor means.
 12. An apparatus as in claim 11 wherein said valveswitching mechanism includes a reciprocal lever means with slotstherein, said rotary member having studs projecting into said slotswhereby reciprocation of said lever means reciprocates said rotary valvemember to shift ports between the intake and discharge strokes of saidpump piston.
 13. An apparatus as in claim 12 wherein said lever means isadapted to be disengaged to a position where it does not reciprocatewhereby either or both pumps may intake and exhaust through only oneport.
 14. An apparatus as in claim 8 wherein said motor means includesmotion translating means adapted to convert rotary motion intoreciprocating arcuate motion and valve switching mechanisms connectingsaid motion translating means with said valve means.
 15. An apparatus asin claim 14 wherein said valve switching mechanisms are adjustable todisengage from said motion translating means and leave either or both ofsaid cylinders communicating with only one port during both the intakeand exhaust stroke of its accompanying piston.
 16. An apparatus as inclaim 15 wherein said motion translating means comprises rotatable cams,vertically reciprocable members having aperture means receiving saidcams and adapted to vertically reciprocate with pauses at the topmostand bottom-most positions upon rotation of said cams, pivot members onsaid vertically reciprocable members and adapted to arcuatelyreciprocate in a vertical plane upon vertical movement of saidvertically reciprocal member to drive said valve switching mechanism.17. An apparatus as in claim 16 wherein said valve switching mechanismincludes pivoted levers driven by said pivot members and adapted toreciprocate in a horizontal plane.
 18. An apparatus as in claim 1wherein each of said cylinder means has two ports and a valve meansadapted to switch communication of said cylinder from one port toanother between the intake and discharge strokes of the piston, saidports having fittings thereon adapted to accommodate flexible conduits.19. An aparatus as in claim 18 wherein said electrical means includes afirst motion translating means adapted to translate rotary motion intosinusoidal reciprocal motion, power transmitting means connecting saidmotor means and said first motion translating means to provide rotationto said motion translating means, a valve switching mechanism, meansoperatively connecting said valve means with said valve switchingmechanism, a second motion translating means adapted to translaterotational movement of said power transmitting means into substantiallyreciprocal movement, said second motion translating means operativelyassociated with said valve switching mechanism and operating it toswitch the valve means between strokes of said pistons, andrEciprocating arm means connected to said pistons and said first motiontranslating means to provide strokes of sinusoidal amplitude to saidpumps.
 20. An apparatus as in claim 19 wherein said pump includes anelongated housing, said cylinder comprising chamber means within saidhousing, port containing means adjacent said chamber means, said portcontaining means including said two port bores, said valve means being arotary member in said housing adjacent said port containing means andadapted to alternately place each port bore in open communication withsaid chamber means, adjustable means associated with said chamber andpiston means to seal said pump against leakage, reciprocal rotatingvalve driving means connected to said valve means and having at leastone driving stud projecting up beyond the end of said housing to engagesaid valve switching mechanism, said valve switching mechanism havingreciprocal lever means engaging said driving stud to operate said valvemeans upon reciprocation thereof.
 21. An apparatus as in claim 1 whereinsaid electrical control means includes means to advance the tube racksautomatically and incrementally upon completion of each pump cycle andmeans to advance the racks without any processing by the tip.
 22. Anapparatus as in claim 1 wherein said electrical control means includesmeans to operate the pump means alone without advancing the tube racks.23. An apparatus as in claim 1 wherein said control means includes meansto automatically shut down the operation of the apparatus if the rackadvancement means is in a jammed condition or if the tip becomesmisaligned.
 24. An apparatus as in claim 1 wherein said base includesmeans to automatically eject a tube rack which has been processed fromthe path of a rack commencing processing.
 25. An apparatus as in claim 1wherein said electrical control means includes means to process only onetube at a time, whereby said control means has to be manuallyreactivated each time to process a plurality of tubes.
 26. A apparatusas in claim 1 wherein said tip raising and lowering means includes awiper means for wiping the tip clean during the upward stroke of saidtip.
 27. A apparatus as in claim 26 wherein said tip raising andlowering means also includes cam and crank arm operated reciprocatingmeans, a first slot means, slide means holding said conduit and tip andmounted for vertical sliding movement in said first slot means andflexible cord means operatively connecting said slide means with saidreciprocating means to raise and lower said tip.
 28. A apparatus as inclaim 27 wherein wiper means comprises pivoted wiping elements adjacentthe vertical path of said tip, cam means on said slide means adapted tocause the wiping elements to converge on said tip during the raisingthereof and a wiping means adapted to provide separate strips of wipingpaper on opposite sides of said tip path, said wiper elements adapted toengage said paper strips and push them against said tip.
 29. A apparatusas in claim 28 wherein said wiping means further comprises a papersupply means, means to advance said paper strips during each cycle ofsaid tip raising and lowering means, said reciprocating means having acam means thereon adapted to engage said paper strip advance means andadvance said paper strips a predetermined distance during each strokethereof whereby an area of dry paper is provided for wiping said tipduring each operational cycle thereof.
 30. An apparatus as in claim 1wherein each of said pump means has two ports and a valve means adaptedto switch communication of said cylinders from one port to anotherbetween the intake and discharge strokes of the pistons, said portshaving fittings thereon adapted to accommodate flexible conduits, saidelectrical means including a motor means, a first motion translatingmeans adapted to translate rotary motion into sinusoidal reciprocalmotion, power transmitting means connecting said motor means and saidfirsT motion translating means to provide rotation to said motiontranslating means, a valve switching mechanism, means operativelyconnecting said valve means with said valve switching mechanism, asecond motion translating means adapted to translate rotational movementof said power transmitting means into substantially reciprocal movement,said second motion translating means operatively associated with saidvalve switching mechanism and operating it to switch the valve meansbetween strokes of said pistons, reciprocating arm means connected tosaid pistons and said first motion translating means to provide strokesof sinusoidal amplitude to said pumps, and a constant force spring, oneend of said spring being bent and fitting into a slot on said firstmotion translating means, the other end of said spring being coiled andhooked around said reciprocating arm means to elminate any looseness orplay in said reciprocating arm means.
 31. An apparatus for selectivelyor automatically processing a plurality of liquid sample containingtubes mounted in a support rack comprising a surface means, rack advancemeans cooperating with said surface means to advance said racks, aliquid metering and dispensing apparatus, a conduit means incommunication with said metering and dispensing means and having anaspirating and dispensing tip, said apparatus adapted to providesinusoidal aspirating and dispensing pressures to said tip only whensaid tip is in the down position, means adapted to raise and lower saidtip into engagement with the samples contained in said tubes, rackejection means adapted to eject processed racks from the path of a rackcommencing processing, said tip raising and lowering means including awiper means for wiping said tip as it is being raised.
 32. An apparatusas in claim 31 including rack guide means adapted to successively guidea plurality of racks into engagement with said rack advance means tocommence processing.
 33. An apparatus as in claim 32 wherein said guidemeans comprises two parallel rails substantially perpendicular to thepath of racks engaged by said rack advance means and being processed,and a rack push bar means mounted between said rails, a tensioning meansconnected to said push bar means and biasing the same to forceunprocessed rack toward said rack advance means.
 34. An apparatus as inclaim 33 wherein said tensioning means comprises a pulley wheel mountedin one of said rails, a cord passing over said wheel with one endconnected to said push bar means and the other end connected to a springmeans.
 35. An apparatus as in claim 31 wherein said rack advancementmeans includes a slot in said surface means and a rack engaging meansmounted for reciprocal movement under said surface means and having atoothed means adapted to project through said slot and engage the bottomof said racks.
 36. An apparatus as in claim 35 wherein said rackengaging means is mounted on a platform under said surface means, a slotin said platform underlying the slot in said surface means and generallyparallel therewith, a slotted guide means mounted on the bottom side ofsaid platform and a slide member mounted in said guide means andcarrying said toothed means.
 37. An apparatus as in claim 31 whereinsaid means for raising and lowering said tip includes a holder foradjustably holding said conduit means adjacent said tip.
 38. Anapparatus as in claim 31 wherein said wiper means comprises a wiperpaper supply means, means providing two srips of said wiper paper oneach side of said tip, means to advance said paper strips and means forpushing said strips against said tip.
 39. An apparatus as in claim 38wherein said means for pushing said paper strips against said tipcomprises a pair of pivotally mounted wiper elements, said means forraising and lowering said tip includes cam means adapted to force saidwiper elements against said tip as it is being raised.
 40. An apparatusas in claim 31 wherein said surface means has a switch meaNs thereinadapted to control the operation of said tip lowering means through saidelectrical control means, said electrical control means adapted toprevent the lowering of said tip when said switch means senses theabsence of a tube.
 41. An apparatus as in claim 31 wherein said rackejection means comprises a pair of flipper elements adapted to shove aprocessed rack laterally out of the path of a rack commencingprocessing, and means to power said flippers.
 42. An apparatus as inclaim 41 including switch means in the path of said racks beingprocessed, said switch means adapted to activate said flipper means whensaid rack contacts said switch.
 43. Apparatus for processing a liquid tobe analyzed comprising a plurality of test tubes, a rack for supportingthe test tubes upright at spaced intervals along the length of the rack,a stationary table having an upwardly facing planar surface on which therack is slidable, a flexible conduit, a downwardly extending tip at theend of the conduit having an opening or bore communicating at its upperend with the passage of the conduit and open at its lower end to allowentry or discharge of liquid through the tip into or out of the conduit,means to support the tip movably above the table comprising means toraise and lower the tip relative to the table, means for intermittentlymoving the rack longitudinally over the table along a path extendingunder the tip, positive displacement pump means comprising a pistonreciprocable in a cylinder communicating with the conduit, pump drivingmeans for intermittently moving the piston in alternate suction andforcing strokes within the cylinder, said driving means having means forinterrupting the motion of the piston at the end of each stroke toprovide a pause for an appreciable time before the next stroke starts,and means for coordinating operation of the several means to carry outone or more cycles, each cycle including the following steps: the rackis moved to bring one of the tubes therein to a position under the tip,the rack is stopped with the tube in that position, the tip is moveddown into the tube under the tip, the piston is moved through one of itsalternate strokes while the tip is in the tube, the piston is stoppedfor its pause, the tip is raised out of the tube, and the piston ismoved through the other of its alternate strokes.
 44. Apparatus inaccordance with claim 43 in which the cylinder has a common port forentry and discharge of liquid with respect to the cylinder, theapparatus comprises another conduit, a member having two fixed passages,one of the passages being connected to and communicating with thefirst-mentioned conduit and the other passage being connected to andcommunicating with the other conduit, valve means for selectivelyconnecting the common port to one of the passages for communicationtherewith, and the operation coordinating means including means foroperating the valve means when the piston is stopped for a pause. 45.Apparatus in accordance with claim 43 comprising means for sensing atube in position below the tip for stopping the rack-moving means. 46.Apparatus in accordance with claim 43 comprising means actuated by arack whose tubes have advanced beyond the tip-position in the path forejecting such rack to an area of the table to one side of the path. 47.Apparatus in accordance with claim 43 comprising means for adjustinglength of piston stroke and indicating means to indicate pump strokevolume.
 48. Apparatus for processing a liquid to be analyzed comprisinga plurality of test tubes, a rack for supporting the test tubes uprightat spaced intervals along the length of the rack, a stationary tablehaving an upwardly facing planar surface on which the rack is slidable,flexible conduit, a downwardly extending tip at the end of the conduithaving an opening or bore communicating at its upper end with thepassage of the conduit and open at its lower end to allow entry ordischarge of liquid through the tip inTo or out of the conduit, means tosupport the tip movably above the table comprising means to raise andlower the tip relative to the table, means for intermittently moving therack longitudinally over the table along a path extending under the tipfrom an initial rack-entry position in the path to a finaleject-position therein, means for sliding the rack laterally on thetable into the initial rack-position in the aforementioned path, meansfor pushing the rack laterally out of the path after the last tube inthe rack passes beyond the tip position, positive displacement pumpmeans comprising a piston reciprocable in a cylinder communicating withthe conduit, pump driving means for intermittently moving the piston inalternate suction and forcing strokes within the cylinder, said drivingmeans having means for interrupting the motion of the piston at the endof each stroke to provide a pause for an appreciable time before thenext stroke starts, and means for coordinating operation of the severalmeans to carry out one or more cycles, each cycle including thefollowing steps: the rack is moved to bring one of the tubes therein toa position under the tip, the rack is stopped with the tube in thatposition, the tip is moved down into the tube under the tip, the pistonis moved through one of its alternate strokes while the tip is in thetube, the piston is stopped for its pause, the tip is raised out of thetube, and the piston is moved through the other of its alternatestrokes.
 49. Apparatus for processing a liquid to be analyzed comprisinga plurality of test tubes, a rack for supporting the test tubes uprightat spaced intervals along the length of the rack, a table having anupwardly facing planar surface on which the rack is slidable, said tablehaving an entrance area, large enough to accommodate several racks, toreceive one or more racks to be processed, an exit area large enough toaccommodate several racks to receive one or more racks after completionof processing, and an area, contiguous to the entrance and exit areas,comprising the rack-processing path, a flexible conduit, a downwardlyextending tip at the end of the conduit having an opening or borecommunicating at its upper end with the passage of the conduit and openat its lower end to allow entry or discharge of liquid through the tipinto or out of the conduit, means to support the tip movably above thetable comprising means to raise and lower the tip relative to the table,means for intermittently moving the rack longitudinally over the tablealong the rack-processing path extending under the tip from an initialrack-entry position in the path to a final eject-position therein, meansfor sliding the rack laterally on the table into the initialrack-position in the aforementioned path, means for pushing the racklaterally out of the path after the last tube in the rack passes beyondthe tip position, positive displacement pump means comprising a pistonreciprocable in a cylinder communicating with the conduit, pump drivingmeans for intermittently moving the piston in alternate suction andforcing strokes within the cylinder, said driving means having means forinterrupting the motion of the piston at the end of each stroke toprovide a pause for an appreciable time before the next stroke starts,and means for coordinating operation of the several means to carry outone or more cycles, each cycle including the following steps: the rackis moved to bring one of the tubes therein to a position under the tip,the rack is stopped with the tube in that position, the tip is moveddown into the tube under the tip, the piston is moved through one of itsalternate strokes while the tip is in the tube, the piston is stoppedfor its pause, the tip is raised out of the tube, and the piston ismoved through the other of its alternate strokes.